Process for preparing coated microbial pesticides and pesticides produced therefrom

Abstract

The present invention provides an improved process for preparing coated microbial pesticides comprising antagonistic microorganisms and natural biopolymer originated from natural sources; and pesticides prepared therefrom.

What is claimed is: 
     
       1. A process for preparing a microbial pesticide which consists essentially of (a) mixing with water and heating a biopolymer selected from the group consisting of microbiologically metabolizable biopolymer-containing natural substances and microbiologically metabolizable biopolymers extracted therefrom, into the form of a gel or paste at a temperature between 80° C. and 121° C., wherein said biopolymer is one or more substances selected from the group consisting of grains, tubers, tuberous roots and starch extracted therefrom; agar; gelatin, polygalacturonic acid; chitosan; carboxymethyl cellulose; gelrite; and natural wax;   (b) cooling said biopolymer gel or paste to a temperature between a room temperature and 60° C.;   (c) mixing one or more antagonistic microorganisms in an amount ranging from about 10 4  to 10 14  cells per gram of the pesticide, in biologically pure cultures, selected from the group consisting of Bacillus subtilis subsp. Krictiensis ATCC 55078 and 55079, Pseudomonas pyrocinia ATCC 15958, Pseudomonas fluorescence ATCC 27663, Gliocladium virens ATCC 52045, Trichoderma reesei ATCC 28217, Trichoderma harzianum ATCC 52445, Trichoderma hamatum ATCC 52198, Trichoderma viride ATCC 52440, Streptomyces cacaoi subsp. asoensis ATCC 19093, Bacillus thuringiensis ATCC 13367, Beauveria bassiana ATCC 26851, 48585 and 48023, Hirsutella thomsonii ATCC 24874, Metarhizium flavoviride ATCC 32969, Verticillium lencanii ATCC 46578 and Collectotrichum gloeosporioides f. sp. jussiaeas ATCC 52634 with said cooled biopolymer gel or paste; and then   (d) formulating and drying the microorganism-biopolymer gel or paste mixture; whereby an unfermented microbial pesticide is produced.   
     
     
       2. The process of claim 1, wherein said heating is carried out at a sterilizing temperature. 
     
     
       3. The process of claim 1, which further comprises: adding one or more microoganism stabilizers selected from the group consisting of glycerol, skim milk, milk, dry milk, plant oil and animal oil and/or one or more nutrient supplements selected from the group consisting of soy bean meal, cotton seed meal, animal peptone, plant peptone, milk, skim milk, chitin powder, compost powder, wheat bran, corn extract, yeast extract, molasses, glucose, sucrose, dextrin, corn syrup, iron, manganese, zinc, cobalt, soil and soil extract either between step(b) and step(c) or during step(c) of claim 1. 
     
     
       4. A coated microbial pesticide prepared from the process in accordance with claim 1. 
     
     
       5. A process for preparing a floatable microbial pesticide which comprises (a) mixing with water and heating a biopolymer selected from the group consisting of microbiologically metabolizable biopolymer-containing natural substances and microbiologically metabolizable biopolymers extracted therefrom, into the form of a gel or paste at a temperature between 80° C. and 121° C.;   (b) cooling said biopolymer gel or paste to a temperature between a room temperature and 60° C.;   (c) mixing one or more antagonistic microorganisms in an amount ranging from about 10 4  to 10 14  cells per gram of the pesticide, in biologically pure cultures, selected from the group consisting of Bacillus subtilis subsp. Krictiensis ATCC 55078 and 55079, Pseudomonas pyrocinia ATCC 15958, Pseudomonas fluorescence ATCC 27663, Gliocladium virens ATCC 52045, Trichoderma reesei ATCC 28217, Trichoderma harzianum ATCC 52445, Trichoderma hamatum ATCC 52198, Trichoderma viride ATCC 52440, Streptomyces cacaoi subsp. asoensis ATCC 19093, Bacillus thuringiensis ATCC 13367, Beauveria bassiana ATCC 26851, 48585 and 48023, Hirsutella thomsonii ATCC 24874, Metarhizium flavoviride ATCC 32969, Verticillium lencanii ATCC 46578 and Collectotrichum gloeosporioides f. sp. jussiaeas ATCC 52634 with said cooled biopolymer gel or paste;   (d) formulating and drying the microorganism-biopolymer gel or paste mixture, to provide a microbial pesticide; and then   (e) coating a natural source, floatable material with said microbial pesticide, wherein said natural source, floatable material is selected from the group consisting of puffed grain, rice bran, nut shell, barley bran, corn husk, wheat straw, barley straw, rice straw, corn stalk, millet stalk, leaves, blades and sawdust;   whereby a floatable microbial pesticide is produced.